Didem Turgut Coşan

Effects of various agents on DNA fragmentation and telomerase enzyme activities in adenocarcinoma cell lines

Natural compounds such as resveratrol, tannic acid, and quercetin may help to treat cancer. Tamoxifen is a non-steroidal anti-estrogen drug widely used in the treatment of patients with estrogen receptor-positive breast cancer. The aim of the study was to compare the effects of these natural compounds and tamoxifen in colon adenocarcinoma (CaCo-2) and breast adenocarcinoma (MCF-7) cell lines, on telomerase enzyme activity, cell viability, number of cells and DNA fragmentation. In this study to determine telomerase enzyme activity was used PCR–ELISA kit. To determine cell viability and number of cells were used tripan blue stain. DNA fragmentation was determined by DNA ladder isolation kit. Tannic acid was more effective than resveratrol, with respect to reduction in telomerase activity, cell viability and cell count in breast adenocarcinoma. Tannic acid and tamoxifen was more effective than resveratrol and quercetin telomerase activity, cell viability and cell count in colon adenocarcinoma. Flavonoids such as resveratrol, tannic acid and quercetin which was studied on, has benefical effects on cancer therapy. These effects such as decreasing telomerase enzyme activity, cell viability and number of cells and inducing DNA fragmentation (apoptosis) must be studied for assist to develop new therapeutic pathways. There should be much more sudies in order to discover resveratrol, tannic acid and quercetin and other potential medicines.

Plasminogen Activator Inhibitor Type-1 Gene 4G/5G Polymorphism in Turkish Adult Patients with Asthma

AIM This study has been performed on asthmatic patients in the Turkish population to determine the frequency of 4G/5G polymorphism genotypes of plasminogen activator inhibitor type-1 gene, and with the aim of examining the role of this polymorphism in asthma development. METHODS Genomic DNA obtained from 165 persons (98 patients with asthma and 67 healthy controls) was used in the study. DNA was multiplied with polymerase chain reaction using 4G and 5G allele-specific primers. Polymerase chain reaction products were assessed with CCD camera by being exposed to 2% agarose gel electrophoresis. Results were evaluated with chi-square test. RESULTS No statistically significant difference between the groups with respect to genotype distribution was found (p > 0.05) in the study. The 4G allele frequency was indicated as 48% and 5G allele was as 52% in patients, whereas this was 50-50% in the control group. CONCLUSION It has been established by this study that 4G/5G polymorphism genotypes of plasminogen activator inhibitor type-1 gene do not play a role in the development of asthma in the Turkish population.

Investigation of Association between Plasminogen Activator Inhibitor Type-1 (PAI-1) Gene 4G/5G Polymorphism Frequency and Plasma PAI-1 Enzyme Activity in Patients with Acute Stroke

AIM This study was carried out to determine if there is any association between plasminogen activator inhibitor type-1 (PAI-1) gene 4G/5G polymorphism and plasma PAI-1 enzyme activity in acute stroke patients. METHODS In this study, 333 genomic DNAs (from 253 acute stroke patients and 80 healthy subjects) were analyzed. Genomic DNAs were prepared from peripheral blood using a saline method. These DNAs were amplified by PCR method using primers specific for 4G and 5G alleles. PCR products were separated by 2% agarose gel electrophoresis and visualized by a charge coupled device (CCD) camera. PAI-1 enzyme activities were measured by ELISA method. The results were evaluated statistically with Students t-test, chi(2)-test, one-way analysis of variance, and stepwise regression analysis. RESULTS In this study, frequency of PAI-1 gene 4G5G genotype was found to be low both in patients and controls. PAI-1 enzyme activities were significantly increased in acute stroke patients compared to controls. Although PAI-1 gene 4G5G genotype frequencies were low, the patients carrying this allele had highest plasma PAI-1 enzyme activity; likewise, although PAI-1 gene 4G4G genotype frequencies were high, the patients carrying this allele had lowest plasma PAI-1 enzyme activities. Homocysteine levels had a positive effect of 65% on plasma PAI-1 enzyme activities. CONCLUSION Consequently, in this study, we may assert that PAI-1 gene, 4G4G and 5G5G genotypes, PAI-1 activity, and homocysteine level determination are significant criteria for identifying patients who are likely to develop stroke; on the other hand, a direct relation does not exist between gene polymorphism and enzyme activity.

Role of phenolic compounds in nitric oxide synthase activity in colon and breast adenocarcinoma.

Cancer chemopreventive agents are designed to reduce the incidence of tumorigenesis by intervening at one or more stages of carcinogenesis. This study aimed to determine the effects of resveratrol (RES) and tannic acid (TA), which are chemopreventive agents, on the nitric oxide synthase (NOS) levels that are effective for development of cancer in colon and breast cancer cell lines. The CaCo-2 (human colon carcinoma cell line) and MCF-7 (Michigan Cancer Foundation-7; human breast adenocarcinoma cell line) cells were grown in the laboratory. RES and TA were used to treat CaCo-2 and MCF-7 cells. Nitric Oxide Synthase Assay Kit was used to determine the NOS enzyme activity of CaCo-2 and MCF-7. Statistical differences between control and RES- and TA-treated cells were calculated using the Students t-test for double comparison. It was observed that NO activity was generally decreased in CaCo-2 and MCF-7 cells, in which RES and TA were applied. Results suggest that the phenolic compounds RES and TA have different effects on NOS enzyme activity of the colon and breast cancer cells.

Plasminogen Activator Inhibitor Type-1 Gene 4G/5G Polymorphism Is Associated with Hypertensive Patients in the Turkish Population

This study has been performed on hypertensive patients in the Turkish population to determine the frequency of 4G/5G polymorphism genotypes of plasminogen activator inhibitor type-1 gene and with the aim of examining the role of this polymorphism in hypertension development. Genomic DNA obtained from 284 persons (176 patients with hypertension and 108 healthy controls) was used in the study. DNA was multiplied by polymerase chain reaction using 4G and 5G allele-specific primers. Polymerase chain reaction products were assessed by being exposed to 2% agarose gel electrophoresis. Results were evaluated with the chi-square test. The 4G allele frequency was 31.25% and the 5G allele frequency was 68.75% in patients, whereas it was 49/51% in a control group. 5G5G genotype was found statistically high (p < 0.001) in patients relative to controls. This study showed that the plasminogen activator inhibitor type-1 gene 4G/5G polymorphism and the 5G5G genotype appear to be associated with an elevated risk of developing hypertension in a representative sample of Turkish population.

Effectiveness of GFAP in Determining Neuronal Damage in Rats with Induced Head Trauma.

AIM To determine whether the serum level of glial fibrillary acidic protein (GFAP), an important indicator of neuron damage, correlates with the extent of tissue damage in the rat with induced head trauma and to obtain data in order to avoid unnecessary cranial computed tomography analyses. MATERIAL AND METHODS Three-month-old male Sprague-Dawley rats were used. Rats were divided into 5 groups. The experimental head trauma model was examined in five groups (n=8) as follows: The control group had no intervention; Group 1: Head trauma was induced by dropping a 25 mg ball from a height of 20 cm; Group 2: Head trauma was induced by dropping a 50 mg ball from a height of 20 cm; Group 3: Head trauma was induced by dropping a 50 mg ball from a height of 80 cm; Group 4: Head trauma was induced by dropping a 100 mg ball from a height of 80 cm. Thus, according to the Newtons Law, respectively 0.05, 0.1, 0.2 and 0.4 N trauma was created. Serum GFAP levels were analyzed and the damage to cerebral tissues was evaluated in all groups. RESULTS We determined that number of apoptotic cells and particularly the number of GFAP (+) protoplasmic astrocytes at the perilesional region of the cortex increased in association with the increased serum GFAP level as long as the severity of the trauma increased. CONCLUSION Serum GFAP concentration can be used as a marker of the severity of head trauma and traumatic brain injury. However, more animal studies are required to reflect this result in clinical practice.

The effect of doxorubicin on rats that received toxic and carcinogenic benzo(a)pyrene.

Benzo(a)pyrene (B(a)P) is a polycyclic aromatic hydrocarbon with carcinogenic and toxic effects. Doxorubicin is a DNA-interacting drug widely used in chemotherapy. In the present study we investigated the effects of doxorubicin on rats that received benzo(a)pyrene. Sprague-Dawley male rats, 3-4 months old, were divided into 5 groups (n=9 per group). Group 1 (controls) received normal saline intraperitoneally (i.p.) and intragastrically (i.g.), Group 2 (controls) similarly received corn oil i.p. and i.g., Group 3 received corn oil soluble benzo(a)pyrene (10mg/kg b.wt every 10 days for 40 days), Group 4 received doxorubicin (4 mg i.p. on 3 consecutive days), Group 5 received doxorubicin for 3 days (as in group 4) followed by benzo(a)pyrene as in group 3. After twenty-four hours urine samples were collected, heart blood, liver and kidney tissue samples were obtained. Biochemical data were evaluated on urine and blood; liver and kidney tissue samples were investigated histologically. Uric acid, urine creatinine, creatine clearance, urea nitrogen, serum creatinine values, serum glutamic oxaloacetic transaminase (SGOT, AST), serum glutamic pyruvic transaminase (SGPT, ALT), alkaline phosphatase (ALP, AP), superoxide dismutase (SOD), catalase (CAT) activities and malondialdehyde (MDA) levels were significantly different in the 3rd group compared with control groups. Most of the parameters group 5 were statistically similar to control values. Histological appearance of the liver and the kidney tissue samples supported the improvement in the 5th group. The result of our study indicated that liver and kidney functions impaired with benzo(a)pyrene may be partially restored by doxorubicin.

miRNA-146a, miRNA-155 and JNK expression levels in peripheral blood mononuclear cells according to grade of knee osteoarthritis.

Osteoarthritis (OA) is the most common joint disease characterized by joint pain and a progressive loss of articular cartilage. OA known as a non-inflammatory disease. Despite this the recent studies are shown synovitis and low inflammation to have a role in OA pathophysiology. The aim of this study to determine the roles of a potential therapeutic targets miRNA-146a, miRNA-155 and JNK expression levels in OA patients. Peripheral mononuclear blood cells (PBMCs) were extracted from OA patients and healthy subjects. The expression levels of miRNA-146a, miRNA-155 and JNK were quantified using by real-time PCR assay. According to study results a statistically significant increase was observed only in miRNA-155 expression level (p=0,039). However, miRNA-146a and miRNA-155 expressions increased in the progressive stages (grade 3 and grade 4) in OA patients. Our data suggests that correlation of miRNAs regulating and signal pathways can play an important role in OA pathogenesis and disease progression.

Estrogen and Androgen Hormone Levels Modulate the Expression of PIWI Interacting RNA in Prostate and Breast Cancer

PIWI interacting RNAs (piRNAs), a member of non-coding RNA, originate from intergenic repetitive regions of the genome. piRNA expressions increase in various cancers and it is thought that this increase could be caused by hormones. We aimed to determine the effects of hormones on piRNA expression in breast and prostate cancer. High viability and a decrease in adhesion were observed at the concentrations of the highest proliferation. Furthermore, an increase in adhesion was also observed in MDA-MB-231 cells. After hormone treatment, while piR-651 expression had increased both breast and prostate cancer cell lines, piR-823 expressions increased in prostate cancer cell lines and only in the breast cancer cell line which was malignant. Thus, it was determined that piR-823 might show different expressions in different type of cancers.

Association of paraoxonase 1 (PON1) gene polymorphisms and concentration with essential hypertension

ABSTRACT Human serum paraoxonase 1 (PON1) is carried by high-density lipoprotein in blood circulation and is shown to be effective in preventing oxidized phospholipids carried by low-density lipoprotein particles, thus it acts as an antioxidant. Polymorphism in this gene has been investigated for many metabolic diseases, but it is not thought to be a genetic risk factor for essential hypertension. The aim of this study was to determine whether there was an association between PON1 gene polymorphisms and concentration with essential hypertension. The study population was comprised of 100 patients with essential hypertension and 100 healthy controls. One promoter region [C(-108)T] and two coding region (Q192R and L55M) polymorphisms in the PON1 gene were genotyped in individuals by using the TaqMan assay. Plasma PON1 concentration in all volunteers was also measured spectrophotometrically by the enzyme-linked immunosorbent assay method. The genotype and allele frequencies of the PON1 C(-108)T polymorphism showed significant differences between the essential hypertensive and control groups (CT vs. CC: p<0.001; T allele vs. C allele: p<0.001). There was no significant difference for the PON1 L55M polymorphism between the groups, while the heterozygote genotype of the PON1 Q192R polymorphism showed significant difference (p = 0.03). The PON1 concentration was also found to be significantly lower in hypertensive patients (p < 0.001). Decline in the level of PON1 gene may be one of the main factors in the development of essential hypertension, and the PON1 C(-108)T polymorphism may have a prognostic value in the patients with essential hypertension.